Simulation Of Ventilation Systems Used In Commercial Kitchens In Winter

At present, due to the lack of necessary studies on commercial kitchen ventilation systems and differences between the designing and utilizing conditions of kitchens such as hotels and eateries, there are so many problems in the commercial kitchen ventilation systems. It is the reason that the position and type of introducing supply air into commercial kitchens and the ratio and velocity of supply air lead to bad working environment. So it is indispensable to study commercial kitchen ventilation systems.Because of the fact that common kitchen ventilation systems design does not effectively remove pollutants, this paper simulates the influences of supply air types of ceilings supply; air-curtain supply and rear supply on the temperature and velocity field and exhaust efficiency in commercial kitchens based on the Airpak 2.0 produced by FLUENT Company. The thesis mostly studies every supply type focusing ratios of supply air volumes to exhaust volumes on 8%, 13%, 18%, 23%, 28% and 33%. This study simulates the ventilation condition of pre-heating supply air to 5℃ and the ratio of 28% and does necessary experiments to validate the model.This research results reveal the trend of exhaust efficiency under ceilings supply, rear supply and air-curtain supply is gradually rising as the ratio of supply air volume to exhaust volume is increasing in commercial kitchen ventilation systems in winter. Under the condition of the same supply air ratio, the exhaust efficiency of air-curtain supply types is highest, that of ceilings supply is higher, and that of rear supply is lowest. If the supply air ratio is same, the mean temperature in the operating area under ceiling supply is highest, that at the bottom of operating area under rear supply is lowest, and that at the top of operating area under air-curtain supply is lowest. Three types all reduce the exhaust efficiency in order to improve the comfort in operating area through pre-heating, but it is not obviouse. The paper helps to achieve the integrative of commercial kitchen design and the optimization of commercial kitchen ventilation system design. The result helps to reduce the operating energy cost of commercial kitchen ventilation systems and improve the environment of operating area.